The Amazing Bulk
I think this has been suggested already, but the suggestion doesn't do it much justice. Here's why I think it should be considered:
Synopsis: As you can probably gather from the title, this is a ripoff of The Incredible Hulk. Hank Howard, a young scientist, is working on a serum to give superhuman ability for General Darwin, who also happens to be the father of Hank's girlfriend, Hannah. Years of failures when making the serum make Darwin very impatient toward Hank. One night, Hank is mugged on a subway in front of Hannah.The incident makes him feel weak, so he uses the serum on himself. The serum turns him into Grimace with a steroid problem when he gets angry. Darwin apprehends Hank, planning to use the newfound powers against the nefarious Dr. Kantlove, a mad scientist who looks like the lovechild of Tim Curry and Dr. Robotnik, when Kantlove threatens to destroy the moon to impress his wife
Why it should be riffed:
1. The special effects. The entire movie is shot in front of a green screen, and all of the backgrounds are taken from free CGI websites that look like they belong in an n64 game. The lack of a real set leads to actors pretending to run, walk, and drive on a stationary platform (at one point, some cops are sitting on a couch with an MS paint police car drawn around it)
2. Comic sans. Comic sans everywhere
3. The nonsensical use of stock animations. Many of the scenes are filled with random CGI characters that have nothing to due with the scene at hand (at the end of the movie, there is a five minute chase sequence with the Bulk being hunted down by modern military tanks and fighter jets along side a pirate ship, a WWI triplane, Robin Hood, Zeus, and an old west cowboy)
In his series The Search For the Worst, youtuber I Hate Everything said that this movie is impossible to enjoy, even ironically. I challenge you to prove him wrong.